Name: training a sophisticated microsurgical technique: interposition of external jugular vein graft in the common carotid artery in rats
Uploaded: 2012-11-11T14:00:00.000+00:00
Duration: 15 min 21 s
Description: Watch this Scientific Journal Video about Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats at JoVE.com

This study was funded by the research promotion program &#34;START&#34; of the medical faculty of RWTH Aachen University, Germany (Title: &#34;Die Arterialisation ven&#246;ser Gef&#228;&#223;e&#34; START 690753). We would like to thank Mrs. Mary-Joan Bl&#252;mich for her excellent editing assistance. Dr. Maria Kokozidou was financed from Fresenius 2011_A61.

1. Experimental Animals
<ol>
 <li>Obtain a Local Ethics Committee approval for all experiments which will be performed, in accordance with the animal protection FELASA guidelines. </li>
 <li>Use female Sprague-Dawley rats available to purchase from any commercial breeder (e.g. Charles River Wiga GmbH, Sulzfeld, Germany). We used 21 animals divided in three groups of 7 animals each that were sacrificed at 3, 6 and 12 weeks postoperatively. At the time of purchase, the animals should be 12 weeks of age and weigh 250-300 g.</li>
 <li>Keep the animals in climate-controlled rooms having an ambient temperature of 21 °C, 60% relative humidity and a 12-hr light-dark cycle with free access to food and water. </li>
</ol>
2. Anesthesia and Operative Preparation
<ol>
 <li>Induce general anesthesia by using a Plexiglas box connected to the anesthesia machine, set at an oxygen flow rate of 1 L/min, and an isofluorane vaporizer with 5 % anesthetic gas. </li>
 <li>Maintain the anesthesia with the isofluorane vaporizer at 1.5 % as soon as the deep sensory reflexes of the animals are suppressed. </li>
 <li>Fix the rats in supine position on a body warming plate. </li>
 <li>Prepare the operation region of each animal by removing its fur with a depilation cream, from the jaw angle down to 2 cm below the manubrium sterni. </li>
 <li>Prepare a sterile surgical field by paying attention to the surgical area, the area prepared on the animal and the front of the surgeon: 
 <ul>
 <li>Clean the benchtop with a disinfectant. </li>
 <li>Prepare the incision site by using multiple applications of surgical scrub solution (e.g. Chlorhexidine and 70% isopropyl alcohol). Apply the Chlorhexidine first, the alcohol second and, finally, the scrub solution. </li>
 <li>Wear a disposable surgical gown and surgical gloves, or alternatively, exam gloves that have been previously washed with a surgical disinfectant. </li>
 </ul>
</li>
 <li>Use sterile microsurgery instruments in the operation procedure. </li>
 <li>Use an operation microscope (Wild Heerbrugg M650, Gais, Switzerland) in 10-20-fold magnification. </li>
</ol>
3. Anatomy
Figure 1 depicts the anatomy of the rat's neck:
1a) Situs before transection of the right sternocleidomastoid muscle.
1b) Situs after transection of the right sternocleidomastoid muscle.
4. Cuff Preparation
Cut the cuffs in a length of 3 mm by hand from a plastic tube (Portex, inner diameter 0.75 mm, outer diameter 0.94 mm, Smiths Medical, UK). These cuffs consist of a tubular cuff body including the complete volume of the plastic tube, and a cuff handle consisting of half of the cuff volume. Both the cuff body and the cuff handle should be equally long. The cuff handle is essential for manipulating the cuff during the surgical procedure. After the cuff is slipped over the vessel, a mini Bulldog clamp is placed simultaneously on the cuff handle and the vessel, in order to prevent from bleeding, keep the cuff in position and ensure stability.
5. Cuff Technique
<ol>
 <li>Slip the cuff over the vessel. </li>
 <li>Immediately afterwards, evert the vessel, pull it over the outside of the cuff body and fix it with a 7-0 silk ligature. In this manner, the lumen of the cuff is covered with endothelium. Thereafter, slip the venous graft over the cuff body and fix it with a new 7-0 silk ligature. To prevent thrombus formation, it is essential to fasten the vein graft tie very close to the cuff margin in order to avoid the blood from contacting the tie holding the artery in place. This is crucial for the distal anastomosis due to the blood flow direction. However, according to the authors, it is not considered essential for the proximal anastomosis for the same reason. </li>
</ol>
6. Surgical Procedure
6.1 Preparation of the right external jugular vein
<ol>
 <li>Make an approximate 2.5 cm-long median cervical incision direct above the manubrium sterni.</li>
 <li>Completely separate a 1 cm-long segment of the right external jugular vein from the surrounding tissues </li>
 <li>Ligate the venous tributaries with 7-0 silk sutures. </li>
</ol>
6.2 Preparation of the right common carotid artery
<ol>
 <li>Prepare the sternocleidomastoid muscle and transect it in the middle.</li>
 <li>Prepare the right common carotid artery carefully, making sure not to compress the artery or the Vagus nerve. Mobilize it from the carotid bifurcation down to the brachiocephalic trunk. </li>
 <li>Subsequently, ligate it twice in the middle with 7-0 silk sutures before transection. </li>
 <li>Slip a nylon cuff consisting of a body and a handle (Figure 2a) over the distal end of the common carotid artery, whereby it is important to ensure that the cuff handle is behind the vessel (Figure 2b).</li>
 <li>Clamp the cuffed end of the distal common carotid artery with a mini Bulldog clamp exactly on the cuff handle to ensure stability (Figure 2c). </li>
 <li>Subsequently, cut the artery directly behind the ligature, whereby the resulting arterial stump should be as long as the cuff body.</li>
 <li>Rinse the arterial lumen with heparin-saline solution (20 IU heparin/ ml 0.9% NaCl). Set a ligation loop aside in the proper position for later use. </li>
 <li>Pull the arterial stump up and slip it like a sleeve over the cuff body. </li>
 <li>Subsequently, pull the ligation loop and knot it tightly.</li>
 <li>To prevent the artery from slipping out of its sleeve, you may implement a trick: grasp both the arterial wall and the suture with the right hand simultaneously and with the left-hand forceps (Figure 2d) make the knot (Figure 2e). </li>
 <li>Repeat the same procedure for the proximal arterial stump (Figure 2f). </li>
</ol>
6.3 Venous graft positioning
<ol>
 <li>Excise a 1 cm-long segment of the clamped external jugular vein </li>
 <li>Since the two cuffed arteries are too far apart from each other for the venous interposition, approximate the correct distance for this procedure using a 3-0 Vicryl-suture which you should loop around each mini Bulldog clamp. </li>
 <li>Criss-cross both sutures.</li>
 <li>Subsequently, pull the sutures in opposite directions, enabling the proper positioning of the cuffed arterial stumps (Figure 2g) </li>
 <li>Rinse the vein segment with the heparin-saline solution. </li>
 <li>Slip one end of the previously reversed vein segment over the cuffed distal carotid artery and secure it in the correct position with a silk 7-0 ligature. </li>
 <li>It is important to note here that the circumference of the vein must be completely and evenly grasped. </li>
 <li>Rinse the vein segment with heparin-saline-solution, and slip the other end of the vein segment over the proximal carotid stump. </li>
 <li>Complete the ligation (Figure 2h); </li>
 <li>Remove the mini Bulldog clamps one after the other, first on the distal carotid artery stump and then on the proximal one, thereby allowing unobstructed blood flow and the arterialization of the venous graft (Figure 2i).
 The surgery is considered successful if blood flow and pulsation are observed within the graft and the common carotid artery (assessed visually). </li>
</ol>
6.4. Wound closure
For the subcutaneous running suture, use 4-0 Vicryl. For a cutaneous running suture, use 3-0 Vicryl.
7. Recovery and Postoperative Management
<ol>
 <li>Let the animals recover from anesthesia on a flat paper bedding under an infrared warming lamp. Do not return the operated animals to the animal holding area until all animals appear normal. </li>
 <li>Postoperatively administer Buprenorphine (Temgesic) in the concentration of 0.03-0.05 mg/kg b.w. sc every 8-12 hr for 2 days. Buprenorphine can be administered just before isofluorane induction. </li>
 <li>Monitor animals postoperatively for their general condition and signs of illness or infections. </li>
</ol>
8. Blood Flow Measurement
The postoperative patency of the graft was proved by blood flow measurement, by using a research Transonic blood flow measurement system (Model: TS420, Transonic Systems Europe B.V., Maastricht, The Netherlands) with a perivascular flowprobe (3 mm, MA3PSB). The system is based on the Doppler principle.
9. Representative Results
By faithfully keeping the instructions aforementioned, the mean duration of the surgical operations was about 65 min. The animals presented an excellent physical condition and gained weight as expected throughout the whole experiment: at the starting point of operation the animals weighed 312±20.39 g. At the sacrifice time point of 3 weeks post-operatively the animals weighed 325.2±28.7 g, at 6 weeks 333±39.9 g and at 12 weeks 362.22±29 g. 
No infections were observed at the operation site and no sores developed. The operation wounds healed completely at the expected time. The neurological control showed no signs of brain infarction or motoric deficiency. The later was an important point since the animals were operated in the carotid artery and one of the two external jugular veins was removed and used as auto-transplant. No allergic reactions to the postoperative pain alleviation therapy were observed. 
All animals were vigilant and social throughout the whole experiment. Their habits concerning receiving food and water remained unchanged throughout the whole time.
The survival rate of all experiments was 100 % at the time point of sacrifice. The graft patency rate was 60 % for the first 10 operated animals and accordingly 82 % for the remaining 11 animals. The total graft patency was 71 %. The blood flow in the arterialized venous grafts was measured at the time point of sacrifice and was 8±3 ml/min without any statistically significant differences between the three sacrifice time points.
<img src="/files/ftp_upload/4124/4124fig1.jpg" alt="Surgical anatomy; labeled arteries, veins, nerves in head dissection, vascular and nerve identification." data-altupdatedat="1747911167000" data-alt="Figure 1"> 
Figure 1. Anatomy of the rat's neck. 1a) Situs before transection of the right sternocleidomastoid muscle. 1b) Situs after transection of the right sternocleidomastoid muscle.
<img src="/files/ftp_upload/4124/4124fig2.jpg" alt="Surgical technique for venous cuff anastomosis, detailed step-by-step procedure with instruments." data-altupdatedat="1747911167000" data-alt="Figure 2"> 
Figure 2. Intraoperative microscopic pictures: a) cuff consisting of cuff-body and cuff-handle; b) cuff slipped over the distal end of the common carotid artery; c) clamping of the cuffed distal common carotid artery stump; d) eversion of the common carotid artery stump over the cuff; e) securing the everted common carotid artery stump with a ligature; f) situs after eversion of both cuffed distal and proximal common carotid artery stumps; g) criss-cross technique for approximation of the two cuffed common carotid artery stumps; h) situs after venous interposition; i) situs after reperfusion of the venous interposition graft.
<img src="/files/ftp_upload/4124/4124fig3.jpg" alt="Venous graft attachment diagram, carotid artery cuffing, surgical technique, vascular surgery illustration." data-altupdatedat="1747911167000" data-alt="Figure 3"> 
Figure 3. Schematic depiction of the situs after reperfusion of the venous interposition graft. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/4124/4124fig3large.jpg" target="_blank"> Click here to view larger figure</a>.

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No conflicts of interest declared.

Interposing an external jugular vein graft in the common carotid artery is a sophisticated microsurgery technique. This video helps the novice surgeon master this technique in minimum time with a lower waste of experimental animals.
Inhalative anesthesia is the best option for this operation, since it avoids an excessively deep anesthesia stage, can be well controlled and allows the surgeon enough time to operate. Moreover the rat is an experimental animal that offers a suitable size to practice such complex surgical techniques much easier, in comparison to the mouse.
The advantage of using the cuff-technique is that vessels with different luminal diameters can be anastomosed. It is important to ligate the complete circumference of the cuffed and everted vessels to avoid bleeding after reperfusion. This model is very suitable to simulate hemodynamics of high blood velocity and low shear stress and to study mechanisms which affect the development of neointimal hyperplasia. The cuff prevents vessel anastomotic remodeling and induces turbulence within the graft and thereby the development of neointimal hyperplasia.
To prevent formation of thrombi, it is essential to place the vein graft tie 2 in a suitable position to prevent association of blood with the tie 1 holding the artery in place (Figure 3).9 Tying the vein graft in the recommended way limits thrombotic events to 12-13% and occlusion of the vessel to even lower proportions.15 As it can seen in the operation video, it is not easy to place the tie exactly in that proposed position. The authors consider it to be crucial for the distal anastomosis, in particular, because of the blood flow direction. By contrast, this is not considered absolutely important for the proximal anastomosis for the same reason.
Unlike the procedure using the caval vein as a graft, this autotransplantation using the external jugular vein as the graft reduces the necessary number of experimental animals by half. Ultimately, interposing an external jugular vein graft in the common carotid artery is a sophisticated microsurgery technique. This video helps the novice surgeon master this technique in minimum time with a lower waste of experimental animals. This model is an excellent means for novice surgeons to practice the cuff-technique that is currently used in solid organ transplantation in small animals.

<table><tbody><tr><td>Braided Silk black 7-0 </td><td>Ethicon Products</td><td>892100</td><td></td></tr><tr><td>Vicryl 3-0</td><td>Ethicon Products</td><td>J285G</td><td></td></tr><tr><td>Vicryl 4-0</td><td>Ethicon Products</td><td>J284G</td><td></td></tr><tr><td>Portex non sterile nylon tubing 0.75 mm, 0.94 mm Fine-Bore Polyethylene (Polythene) Tubing</td><td>Portex UK</td><td>800/200/175/100</td><td></td></tr><tr><td>Isofluorane 5 %</td><td></td><td></td><td>Any genericon</td></tr><tr><td>Heparin</td><td></td><td></td><td>Any genericon</td></tr><tr><td>0.9% saline</td><td></td><td></td><td>Any genericon</td></tr><tr><td>Buprenorphine</td><td></td><td></td><td>Any genericon</td></tr></tbody></table>

training a sophisticated microsurgical technique: interposition of external jugular vein graft in the common carotid artery in rats

Neointimal hyperplasia is one the primary causes of stenosis in arterialized veins that are of great importance in arterial coronary bypass surgery, in peripheral arterial bypass surgery as well as in arteriovenous fistulas.1-5 The experimental procedure of vein graft interposition in the common carotid artery by using the cuff-technique has been applied in several research projects to examine the aetiology of neointimal hyperplasia and therapeutic options to address it. 6-8 The cuff prevents vessel anastomotic remodeling and induces turbulence within the graft and thereby the development of neointimal hyperplasia.
Using the superior caval vein graft is an established small-animal model for venous arterialization experiment.9-11 This current protocol refers to an established jugular vein graft interposition technique first described by Zou et al., 9 as well as others.12-14 Nevertheless, these cited small animal protocols are complicated.
To simplify the procedure and to minimize the number of experimental animals needed, a detailed operation protocol by video training is presented. This video should help the novice surgeon to learn both the cuff-technique and the vein graft interposition. Hereby, the right external jugular vein was grafted in cuff-technique in the common carotid artery of 21 female Sprague Dawley rats categorized in three equal groups that were sacrificed on day 21, 42 and 84, respectively. Notably, no donor animals were needed, because auto-transplantations were performed. The survival rate was 100 % at the time point of sacrifice. In addition, the graft patency rate was 60 % for the first 10 operated animals and 82 % for the remaining 11 animals. The blood flow at the time of sacrifice was 8&plusmn;3 ml/min. In conclusion, this surgical protocol considerably simplifies, optimizes and standardizes this complicated procedure. It gives novice surgeons easy, step-by-step instruction, explaining possible pitfalls, thereby helping them to gain expertise fast and avoid useless sacrifice of experimental animals.

Watch this Scientific Journal Video about Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats at JoVE.com

Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats

Neointimal hyperplasia is the primary cause of stenosis in arterialized veins. We propose a new protocol whereby the right external jugular vein is grafted using the cuff technique in the common carotid artery of Sprague Dawley rats. The survival rate was 100 % at the time point of sacrifice.

Neointimal hyperplasia is one the primary causes of stenosis in arterialized veins that are of great importance in arterial coronary bypass surgery, in ...

training-sophisticated-microsurgical-technique-interposition-external

Nanyang Technological University

Research

JoVE Journal

Medicine

20.4K Views.  University Hospital RWTH Aachen. Neointimale hyperplasie is de primaire oorzaak van vernauwing in aderen arterialized. Wij stellen een nieuw protocol waarbij de juiste externe halsader is geënt met behulp van de manchet techniek in de gemeenschappelijke halsslagader van Sprague Dawley ratten. De overleving was 100% op het tijdstip van het offer.

Video: Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats

Catheterization of the Carotid Artery and Jugular Vein to Perform Hemodynamic Measures, Infusions and Blood Sampling in a Conscious Rat Model

The success of a small animal model to study critical illness is, in part, dependent on the ability of the model to simulate the human condition. Intra-tracheal inoculation of a known amount of bacteria has been successfully used to reproduce the pathogenesis of pneumonia which then develops into sepsis. Monitoring hemodynamic parameters and providing standard clinical treatment including infusion of antibiotics, fluids and drugs to maintain blood pressure is critical to simulate routine supportive care in this model but to do so requires both arterial and venous vascular access. The video details the surgical technique for implanting carotid artery and common jugular vein catheters in an anesthetized rat. Following a 72 hr recovery period, the animals will be re-anesthetized and connected to a tether and swivel setup attached to the rodent housing which connects the implanted catheters to the hemodynamic monitoring system. This setup allows free movement of the rat during the study while continuously monitoring pressures, infusing fluids and drugs (antibiotics, vasopressors) and performing blood sampling.

Vascular accesses to measure hemodynamics, provide fluids and perform blood sampling are important to any small animal model study. We present a technique for implanting catheters into the carotid artery and the common jugular vein in an anesthetized rat for connecting to a system to perform monitoring, infusions and sampling.

The success of a small animal model to study critical illness is, in part, dependent on the ability of the model to simulate the human condition. ...

Performing Permanent Distal Middle Cerebral with Common Carotid Artery Occlusion in Aged Rats to Study Cortical Ischemia with Sustained Disability

Stroke typically occurs in elderly people with a range of comorbidities including carotid (or other arterial) atherosclerosis, high blood pressure, obesity and diabetes. Accordingly, when evaluating therapies for stroke in animals, it is important to select a model with excellent face validity. Ischemic stroke accounts for 80% of all strokes, and the majority of these occur in the territory of the middle cerebral artery (MCA), often inducing infarcts that affect the sensorimotor cortex, causing persistent plegia or paresis on the contralateral side of the body. We demonstrate in this video a method for producing ischemic stroke in elderly rats, which causes sustained sensorimotor disability and substantial cortical infarcts. Specifically, we induce permanent distal middle cerebral artery occlusion (MCAO) in elderly female rats by using diathermy forceps to occlude a short segment of this artery. The carotid artery on the ipsilateral side to the lesion was then permanently occluded and the contralateral carotid artery was transiently occluded for 60 min. We measure the infarct size using structural T2-weighted magnetic resonance imaging (MRI) at 24 hr and 8 weeks after stroke. In this study, the mean infarct volume was 4.5% &#177; 2.0% (standard deviation) of the ipsilateral hemisphere at 24 hr (corrected for brain swelling using Gerriet&#8217;s equation, n = 5). This model is feasible and clinically relevant as it permits the induction of sustained sensorimotor deficits, which is important for the elucidation of pathophysiological mechanisms and novel treatments.

Here we present a protocol to produce permanent distal middle cerebral artery occlusion in elderly female rats with simultaneous occlusion of the carotid arteries to generate large cortical infarcts and sustained deficits. We show confirmation of the lesion size using structural MRI at 24 hr and 8 weeks after stroke.

Stroke typically occurs in elderly people with a range of comorbidities including carotid (or other arterial) atherosclerosis, high blood pressure, ...

A Rat Carotid Balloon Injury Model to Test Anti-vascular Remodeling Therapeutics

The rat carotid balloon injury is a well-established surgical model that has been used to study arterial remodeling and vascular cell proliferation. It is also a valuable model system to test, and to evaluate therapeutics and drugs that negate maladaptive remodeling in the vessel. The injury, or barotrauma, in the vessel lumen caused by an inflated balloon via an inserted catheter induces subsequent neointimal growth, often leading to hyperplasia or thickening of the vessel wall that narrows, or obstructs the lumen. The method described here is sufficiently sensitive, and the results can be obtained in relatively short time (2 weeks after the surgery). The efficacy of the drug or therapeutic against the induced-remodeling can be evaluated either by the post-mortem pathological and histomorphological analysis, or by ultrasound sonography in live animals. In addition, this model system has also been used to determine the therapeutic window or the time course of the administered drug. These studies can leadto the development of a better administrative strategy and a better therapeutic outcome. The procedure described here provides a tool for translational studies that bring drug and therapeutic candidates from bench research to clinical applications.

The rat carotid balloon injury model described below allows researchers to evaluate drugs or therapeutics that negate injury-induced arterial hyperplasia. Detailed pre-surgical preparation, surgical procedure, and post-surgical cares of the animal are described.

The rat carotid balloon injury is a well-established surgical model that has been used to study arterial remodeling and vascular cell proliferation. It is ...

A Rabbit Model of Durable Transgene Expression in Jugular Vein to Common Carotid Artery Interposition Grafts

Vein graft bypass surgery is a common treatment for occlusive arterial disease; however, long-term success is limited by graft failure due to thrombosis, intimal hyperplasia, and atherosclerosis. The goal of this article is to demonstrate a method for placing bilateral venous interposition grafts in a rabbit, then transducing the grafts with a gene transfer vector that achieves durable transgene expression. The method allows the investigation of the biological roles of genes and their protein products in normal vein graft homeostasis. It also allows the testing of transgenes for the activities that could prevent vein graft failure, e.g., whether the expression of a transgene prevents the neointimal growth, reduces the vascular inflammation, or reduces atherosclerosis in rabbits fed with a high-fat diet. During an initial survival surgery, the segments of right and left external jugular vein are excised and placed bilaterally as reversed end-to-side common carotid artery interposition grafts. During a second survival surgery, performed 28 days later, each of the grafts is isolated from the circulation with vascular clips and the lumens are filled (via an arteriotomy) with a solution containing a helper-dependent adenoviral (HDAd) vector. After a 20-min incubation, the vector solution is aspirated, the arteriotomy is repaired, and flow is restored. The veins are harvested at time points dictated by individual experimental protocols. The 28-day delay between the graft placement and the transduction is necessary to ensure the adaptation of the vein graft to the arterial circulation. This adaptation avoids rapid loss of transgene expression that occurs in vein grafts transduced before or immediately after grafting. The method is unique in its ability to achieve durable, stable transgene expression in grafted veins. Compared to other large animal vein graft models, rabbits have advantages of low cost and easy handling. Compared to rodent vein graft models, rabbits have larger and easier-to-manipulate blood vessels that provide abundant tissue for analysis.

This method describes the placement of interposition vein grafts in rabbits, the transduction of the grafts, and the achievement of durable transgene expression. This allows the investigation of physiological and pathological roles of transgenes and their protein products in grafted veins, and testing of gene therapies for vein graft disease.

Vein graft bypass surgery is a common treatment for occlusive arterial disease; however, long-term success is limited by graft failure due to thrombosis, ...

Mouse Heterotopic Cervical Cardiac Transplantation Utilizing Vascular Cuffs

Murine models of cardiac transplantation are frequently utilized to study ischemia-reperfusion injury, innate and adaptive immune responses after transplantation, and the impact of immunomodulatory therapies on graft rejection. Heterotopic cervical heart transplantation in mice was first described in 1991 using sutured anastomoses and subsequently modified to include cuff techniques. This modification allowed for improved success rates, and since then, there have been multiple reports that have proposed further technical improvements. However, translation into more widespread utilization remains limited due to the technical difficulty associated with graft anastomoses, which requires precision to achieve adequate length and caliber of the cuffs to avoid vascular anastomotic twisting or excessive tension, which can result in damage to the graft. The present protocol describes a modified technique for performing heterotopic cervical cardiac transplantation in mice which involves cuff placement on the recipient's common carotid artery and the donor's pulmonary artery in alignment with the direction of the blood flow.

Mouse cardiac transplantation models represent valuable research tools for studying transplantation immunology. The present protocol details mouse heterotopic cervical cardiac transplantation that involves the placement of cuffs on the recipient's common carotid artery and the donor's pulmonary artery trunk to allow for laminar blood flow.

Murine models of cardiac transplantation are frequently utilized to study ischemia-reperfusion injury, innate and adaptive immune responses after ...

Immunology and Infection

A Rabbit Venous Interposition Model Mimicking Revascularization Surgery using Vein Grafts to Assess Intimal Hyperplasia under Arterial Blood Pressure

Although vein grafts have been commonly used as autologous grafts in revascularization surgeries for ischemic diseases, the long-term patency remains poor because of the acceleration of intimal hyperplasia due to the exposure to arterial blood pressure. The present protocol is designed for the establishment of experimental venous intimal hyperplasia by interposing rabbit jugular veins to the ipsilateral carotid arteries. The protocol does not require surgical procedures deep in the body trunk and the extent of the incision is limited, which is less invasive for the animals, allowing long-term observation after implantation. This simple procedure enables researchers to investigate strategies to attenuate the progression of intimal hyperplasia of the implanted vein grafts. Using this protocol, we reported the effects transduction of microRNA-145 (miR-145), which is known to control the phenotype of vascular smooth muscle cells (VSMCs) from the proliferative to the contractile state, into harvested vein grafts. We confirmed the attenuation of intimal hyperplasia of vein grafts by transducing miR-145 before implantation surgery through the phenotype change of the VSMCs. Here we report a less invasive experimental platform to investigate the strategies that can be used to attenuate intimal hyperplasia of vein grafts in revascularization surgeries.

The present protocol aims to experimentally create venous intimal hyperplasia by subjecting veins to arterial blood pressure for developing strategies to attenuate venous intimal hyperplasia following revascularization surgery using vein grafts.

Although vein grafts have been commonly used as autologous grafts in revascularization surgeries for ischemic diseases, the long-term patency remains poor ...

Microsurgical Skills of Establishing Permanent Jugular Vein Cannulation in Rats for Serial Blood Sampling of Orally Administered Drug

Blood sampling in small laboratory animals is necessary for pharmaceutical lead optimization but can cause great harm and stress to experimental animals, which could potentially affect results. The jugular vein cannulation (JVC) in rats is a widely used model for repeated blood collection but requires adequate training of surgery skills and animal care. This article details the microsurgical procedures for establishing and maintaining a permanent JVC rat model with specific focus on the placement and sealing of the jugular cannula. The importance of monitoring physiological (e.g., body weight, food, and water intake) and hematological parameters, was highlighted with results presented for 6 days post-surgery during the rat&#39;s recovery. The drug-plasma concentration-time profile of orally administered natural phenol ellagic acid was determined in the JVC rat model.

Detailed microsurgical techniques are demonstrated to establish a longer-term jugular vein cannulation rat model for sequential blood collection in the same animal. Physiological and hematological parameters have been monitored during the rat's recovery phase. This model has been applied to study pharmacokinetics of orally administered polyphenol without inducing animal stress.

Blood sampling in small laboratory animals is necessary for pharmaceutical lead optimization but can cause great harm and stress to experimental animals, ...

Modified MCAO/R Model with Preserved ECA for Enhanced Reperfusion and Stability

A Modified Model Preparation for Middle Cerebral Artery Occlusion Reperfusion

The middle cerebral artery occlusion reperfusion (MCAO/R) model is crucial for understanding the pathological mechanisms of stroke and for drug development.However, among the commonly used modeling methods, the Koizumi method often faces scrutiny due to its ligation of the common carotid artery (CCA) and its inability to achieve adequate reperfusion. Similarly, the Longa method has been criticized for disconnecting and ligating the external carotid artery (ECA). This study aims to introduce a modified model preparation method that preserves the integrity of the ECA, involves inserting a monofilament nylon suture through the CCA, repairing the ligated CCA incision, and maintaining reperfusion from the CCA. Reperfusion of blood flow was confirmed using laser speckle flow imaging. Evaluation methods such as the Longa scale, Modified Neurological Severity Score, triphenyltetrazolium chloride (TTC) staining, and immunofluorescence labeling of neurons demonstrated that this approach could induce stable ischemic nerve damage. This modified MCAO/R model protocol is simple and stable, providing valuable guidance for practitioners in the field of cerebral ischemia.

Author Spotlight: A Novel Approach to Cerebral Ischemia Modeling &#8211; Enhancing Reperfusion and Simplifying Procedure

This protocol describes the process of preparing for middle cerebral artery occlusion reperfusion via the common carotid artery.

The middle cerebral artery occlusion reperfusion (MCAO/R) model is crucial for understanding the pathological mechanisms of stroke and for drug ...

Jugular Vein Graft Harvest From a Rabbit Model: A Surgical Procedure to Excise a Segment of Rabbit Jugular Vein for Ex Vivo Studies

Source: Nishio, H., et al. <a href="https://www-jove-com.remotexs.ntu.edu.sg/v/60931">A Rabbit Venous Interposition Model Mimicking Revascularization Surgery using Vein Grafts to Assess Intimal Hyperplasia under Arterial Blood Pressure</a> J. Vis. Exp. (2020).
In this video, we demonstrate a procedure for surgically harvesting a segment of the jugular vein from a rabbit model. The resected segment can be used as an autologous vein graft to study intimal hyperplasia that develops due to arterial blood pressure.

Source: Nishio, H., et al. A Rabbit Venous Interposition Model Mimicking Revascularization Surgery using Vein Grafts to Assess Intimal Hyperplasia under ...

JoVE Encyclopedia of Experiments

Biology

Large Animal Models

Leporine

Carotid Artery and Jugular Vein Interposition: A Technique to Induce Venous Intimal Hyperplasia in Rabbit Model

To interpose the carotid artery with the harvested jugular vein, expose a 20 to 30-millimeter segment of the ipsilateral carotid artery, and separate the artery carefully from the nearby vein and nerve. Ligate all of the branches of the exposed vein with a 4-0 silk suture, and intravenously administer 200 IU/kg of heparin sodium.
Clamp the proximal and distal ends of the artery with surgical rubber clamps, and cut the artery between the clamps. Inject normal saline into the incised carotid artery proximally and distally to distend the artery, and place the harvested vein near the artery to anastomose the vessel in a reversed end-to-end fashion.
To anastomose the proximal end of the vein to the distal end of the artery, place two anchor stitches of 8-0 polypropylene at the site and the opposite site. Add stitches to the upper side of the anastomosis line between the anchor stitches. Flip the artery and the vein graft upside down, and add stitches on the remaining part of the anastomosis line.
Next, remove the intravenous catheter from the vein, and clamp the vein graft proximally. Declamp the carotid artery distally, and observe whether the vein graft expands gradually. Using 8-0 polypropylene interrupted sutures, anastomose the distal end of the vein to the proximal end of the artery, and declamp the artery to check for bleeding from the anastomosis sites.
Finally, ligate the internal carotid artery with a 4-0 silk suture to simulate a poor runoff condition, and to facilitate intimal hyperplasia. Then, clean the wound with saline. Close the incision with 3-0 polyglactin 910 in layers, and allow the rabbit to fully recover with monitoring before returning the animal to its home cage.

Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats

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